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3 outbound dma transactions, 4 outbound function number – Intel CONTROLLERS 413808 User Manual

Page 250

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Intel

®

413808 and 413812—Address Translation Unit (PCI Express)

Intel

®

413808 and 413812 I/O Controllers in TPER Mode

Developer’s Manual

October 2007

250

Order Number: 317805-001US

3.3.2.3

Outbound DMA Transactions

The ATU provides all ADMA channels with a transparent path through the PCI Express

interface. The entire 64-bit Host I/O Interface address programmed in the DMA

descriptor is passed to the PCI Express link unmodified.

3.3.2.4

Outbound Function Number

The 4138xx is a multi-function device and the ATU associates each transaction with the

correct PCI Express function number according to the following algorithm:

• Outbound Configuration transactions use the function number field specified in the

“Outbound Configuration Cycle Function Number - OCCFN” on page 383

.

• Outbound I/O transactions use the function number field specified in the

“Outbound

I/O Base Address Register - OIOBAR” on page 371

.

• Outbound transactions targeting the outbound memory windows utilize the

“Outbound Window x Function Number Mapping” programmed into bits 30:28 of

the associated OUMBARx registers

• Outbound ADMA transactions use the “Host I/O Interface Function Number”

programmed in the ADMA byte count register.